Spin-on tri-layer approaches to high NA 193-nm lithography

Autor: Woo-Kyu Kim, Ping-Hung Lu, Ralph R. Dammel, Lyudmila Pylneva, Ruzhi Zhang, Shinji Miyazaki, Douglas Mckenzie, David J. Abdallah, John J. Biafore, Dalil Rahman, Allen Timko, Frank Houlihan, Hengpeng Wu, Mark Neisser, Alberto D. Dioses
Rok vydání: 2007
Předmět:
Zdroj: SPIE Proceedings.
ISSN: 0277-786X
Popis: New challenges face ArF bottom antireflection coatings (BARCs) with the implementation of high NA lithography and the concurrent increase use of spin-on hard masks. To achieve superior reflectivity control with high NA at least two semi-transparent ARC layers, with distinct optical indices, are necessary to effectively lower substrate reflectivity through a full range of incident angles. To achieve successful pattern transfer, these layers in conjunction with the organic resist, should be stacked with an alternating elemental composition to amplify vertical resolution during etch. This will circumvent the inherent low etch resistance of ArF resist and the decreasing film thicknesses that accompanies increasing NA. Thus, incorporating hard mask properties and antireflection properties in the same two layer system facilitates pattern transfer as a whole rather than just enhancing lithography. As with any material expected to exhibit multiple roles there is a delicate balance between optimizing materials with respect to one of its roles while not impairing its other roles. We will discuss some of these conflicts and present Si-BARCs and carbon rich underlayers which aim to balance these conflicts. In this paper we will explore simulations aimed at finding the best film thicknesses and optical indices, etch rate selectivity, and lithographic performance of high silicon content and high carbon content BARC materials designed to meet the demands of both high NA lithography and trilayer processing.
Databáze: OpenAIRE